Electric socket



Aug. l5', l G, B VBENANDER .2,169,868 v ELECTRvIG SOCKET Filed Mayl, 1937 is lllll HM? Inventor: George B. B erwan'der,

His Attorney Patented Aug. 15, 1939 2,139,858'

UNITED STATES PATENT Oli'FiCl.

ELECTRIC SOCKET George B. Benander, Yalesville, Conn., assignor to Monowatt Electric Corporation, Bridgeport, Conn., a corporation of Connecticut Application May 4, 1937, Serial No. 140,636 Claims. (o1. 17e- 354) 'I'he present invention relates to electric sockets. clearance hole in the boss (not shown). The The objectl of my invention is to provide an upper edge of the strip I1 is substantially flush improved construction and arrangement in elecwith the surface of the housing part I. The strip tric sockets and in particular to provide a socket I'I is preferably preformed and attached to the 5 construction in which all the exposed parts may screw shell after which the screw shell and strip 5 be made of molded insulating material. are inserted as a unit in the housing part I. A

For a consideration of what I believe to be strip 25 of insulating material is arranged benovel and my invention attention is directed to tween the contact strip Il and the inner surface e the following description and the claims appendof the groove I8 and the boss I9. This strip ed thereto. :insulatesv the contact strip from the interior of l0 Referring to the drawing, Fig. 1 is an elevation the chamber 9 in which the pull switch is of a pull chain socket embodying my invention; mounted. Fig. 2 is a sectional elevation of the socket; Fig. 3 In the center of the wall 4 is a contact strip is a plan View of one of the housing parts; Fig. 3a having a U-shaped portion 26 which fits over the is a top plan view of the ratchet member for the upper edge of the wall. The arm 2'! of the U- 15 pull switch; Fig. 4 is a plan View of the other shaped portion tsin a groove 28 in the front housing part; Fig. 5 is a sectional elevation of the side of the wall. The bottom of the U-shaped cap enclosing one end of the socket; Fig. 6 is a portion ts in a depression in the upper edge of bottom plan view of the cap; Fig. 7 is a perspecthe wall so that its outer surface is substantially tive View of the split ring which secures the cap flush with the edge of the wall. The arm 29 20 to the socket housing; and Fig. 8isa fragmentary of the U-shaped portion is flush with the rear sectional View of a portion of the flexible cord side of the wall. When the housing parts are which operates the pull switch. secured together the edge of the wall 6 holds the Referring to the drawing, the electric socket contact strip 26 securely in place. Extending has a longitudinally split housing comprising from the end of the arm 21 is an angular por- 25 semi-cylindrical mating housing parts I and 2 of tion terminating in a circular portion 38 which suitably molded insulating material. The housserves as the center terminal socket. The center ing part I is provided with transverse walls 3 and terminal is spaced from the front side of the 4 which abut transverse walls 5 and 6 on the Walls 4 and 6 and due to its inherent resilience 30 housing part 2 and divide the housing into a can yield to provide a resilient Contact with the 30 chamber 'I for receiving a screw shell 8 and a center contact of a plug threaded in the shell. chamber 9 for housing a pull switch I0. In the Integral with the arm 29 is a contact 3|a which abutting surfaces of the Walls 4 and 6 are fixed rests on an inclined surface 3l of a cam or dowel pins II the projecting ends of which fit in ratchet n member 32 molded integral with the 35 holes I2 and secure the housing parts. together. housing part I. As shown in Fig. 3a the ratchet 35 If the friction between the dowel pins and the comprises four equally spaced inclined surfaces holes is insucient to hold the housing parts to- 3|, 33, 34 and 35, each of the surfaces being ingether, the outer surfaces of the dowel pins may clined circumferentially upward in a counterbe serrated or roughened to increase the friction. clockwise direction as viewed in Fig. 3a. Between The screw shell 8 at its mouth has an outwardthe end of each of the inclined portions and the 40 ly extending peripheral flange I3 which fits in beginning of the succeeding inclined portion is a grooves I4 in the housing parts. The grooves vertical shoulder 36. Onthe inclined portion 34, are provided with filled-in portions I5 which codiametrically opposite the inclined portion 3l, is operate with notches I6 in the flange I3 to no-na contact 31 at one end of a contact strip 33.

rotatably hold the screw shell in the housing. A From the contact 37 the Contact strip extends 45 strip conductor il is fixed at one end to the outangularly to the inner face of the wall 3, vertiside screw shellV and extends through a groove cally upward along the inner face o-f the wall,

I8 between the wall 4 and the side wall of the through a groove 39 in the upper edge of the housing, along the side wall of the housing, bewall, and over the upper surface of a boss identitween aboss I9 and the corner ZiLalong the inner cal with the boss 22. A terminal screw 4E] is 50 face of the end wall 3, and through a groove 2| threaded into the outer end of the contact strip. in the upper edge of the wall 3. The other end Threaded into the center of the ratchet memof the contact strip extends over a boss 22 and ber 32 is a spindle 4I onwhich is rotatablycarhas aterminal screw 23 threaded therein. The ried a disk 42 ofinsulating material having inner end of the terminal screw extends within a equally spaced notches 43 in its periphery. Fixed 55 to the under side of the disk 42 is a bridging member 44 having diametrically opposed contacts 45 having an inclination corresponding to the inclination of the inclined surfaces of the ratchet member. When the bridging member is in the position shown in Fig. 2 the contacts 45 rest on the contacts 3Ia and 31 and complete a circuit between the line terminal 40 and the center contact 30. When the bridging member is moved from this position, the contacts 45 rest on the inclined surfaces 33 land 35 thereby interrupting the circuit to the center contact. A disk 46 of insulating material carried by the bridging member closely adjacent the contacts 45 tends to restrict the arc between the contacts upon breaking the circuit. On the upper side of the disk 42 is an operating arm 41 having diametrically opposed ears 48 the edges of which are downwardly inclined and are adapted to engage the edges of the slots 43 as the arm is turned in a counterclockwise direction as viewed in Fig. 3. When the arm is turned in a clockwise direction the ears slide over the slots 43 Without turning the disk 42. The operating arm 41 is urged in a clockwise direction, as viewed in Fig. 3, and is pressed against the upper surface of the `disk 42 by a coil spring 49 one end of which is hooked over a projection 50 on the operating arm and the other end of which is hooked over a projection 5I on a member 52 which is non-rotatably held against the head 53 of the spindle 4I. The coil spring 48 exerts a force which presses the contacts 45 of the bridging member downward against the inclined surfaces of the ratchet member.

Connected to` the operating member 41 is a iiexible cord 53EL having beads 54 of insulating material molded thereon. During the molding operation the material of the beads thoroughly impregnates the cord providing a cord which is well insulated under all conditions. For eX- ample, the insulating properties of the cord are not destroyed by such a severe test as soaking the cord in water. This is due to the fact that the material of the beads thoroughly impregnates the cord.

From the operating member 41 the cord extends through a flared mouth 55 formed by mating parts molded integral with the housing parts I and 2. A large bead 5B limits the inward motion of the cord. Upon pulling the cord the operating arm 41 is moved through an angle slightly greater than 90. During this movement the ears 48 on the operating arm engage the edges of notches 43 and turn the disk 42 and the bridging member fixed thereto. Upon release of the cord the operating member 41 is returned by the spring 49 to the position shown in Fig. 3, the ears 48 riding over the notches 43 without turning the disk 42. It is, therefore, apparent that by pulling and releasing the cord, the bridging member is turned in 90 steps successively making and breaking the circuit to the center contact.

In the assembly of the socket the screw shell, the switch, and the contacts are assembled in the housing part I. The housing part 2 is then aligned with the housing part I, the dowel pins II fitting in the openings I2, and the housing parts are pressed together. When the housing parts are assembled the screw shell is securely held therebetween, the center contact is clamped between the walls 4 and and the contacts I1 and 38 are clamped between the walls 3 and 5. The outer ends of the contacts I1 and 38 are rigidly held against the bosses 22. The socket is very easy to wire since the line terminal screws 23 and 40 are accessible from the outside of the housing. The line terminals are the only exposed conducting parts of the socket.

For enclosing the line terminals a cap 51 of molded insulating material is provided The surface of the cap which abuts the lower end of the housing is provided with diametrically opposed projections 58 which t into complementary recesses (Fig. 2) in the housing and locate the angular position of the cap with reference to the housing. On the outer surface of the projections 58 are projections 59 which project beyond the outer surfaces of the housing. Integral with the housing parts I and 2 and intermediate the projections 59 are similar projections 60. The projections 59 and G0 cooperate with openings EI in a split ring 62. When the ring is snapped in place the projections 59 and 60 t in the opening 6 I, thereby securing the cap to the housing. Since the openings and projections are circumferentially spaced, the cap is nonrotatably held on the housing.

At the center of the cap is a boss 63 having internally threaded opening 64 molded therein by means of which the cap may be threaded on a suitable support, such as a conduit through which the line conductors extend. In the inner face of the cap is molded an open ended slot or recess 65 of the same width as a nut 66. When the nut B6 is dropped in the slot it is non-rotatably held therein. A screw 61 threaded from the outside of the boss 63 through the nut provides a set screw for xing the cap to the support on which it is threaded. This provides a convenient arrangement for mounting a set screw in a cap of molded insulating material without resorting to the use of molded inserts.

On the upper end of the housing parts I and 2 adjacent the mouth of the screw shell are molded cooperating threads 68 on which a xture may be threaded.

In the use of the socket, the cap 51 is disconnected from the socket housing and is threaded on the end of a conduit and locked in. place by means of the set screw 61. The line conductors which project through the end of the conduit are then connected to the terminals 23 and 4D. It will be noted that these terminals are easily accessible and that they constitute the only exposed conducting parts of the socket housing. The socket housing is now tted on the cap and secured thereto by means of the split ring 62.

What I claim as new and desire to secure by Letters Patent of the United States, is:

l. In an electric socket, a housing, a cap at one end of the housing, circumferentially spaced projections on said cap and said housing respectively, and a. split ring having circumfcrentially spaced openings into which said projections t for securing the cap to the housing.

2. In an electric socket, a housing, a cap at one end of the housing, a split ring encircling said cap and said housing, and circumferentially spaced interiitting portions respectively in said ring and said cap and in said ring and said housing whereby the ring holds the cap on the housing.

3. In an velectric socket, a longitudinally split housing having mating parts of insulating material, socket terminals in the housing comprising a screw shell and a center contact, abutting Walls integral with said housing Aparts providing a chamber Vfor the socket terminals, abutting end Walls on said housing parts closing the end of the housing, bosses on the outside of said end Walls, line terminals for connection with line conductors on said bosses and contact strips for connecting the line and socket terminals extending from the line terminals between the abutting walls of said housing parts, a cap of insulating material on the end of said housing enclosing the line terminals, and means including a split ring embracing said housing parts for non-rotatably and removably securing said cap to said housing.

4. In an electric socket, a longitudinally split housing having mating parts of insulating material, socket terminals comprising screw shell and a center contact in said housing, abutting walls integral with said housing parts providing a chamber for the socket terminals and a chamber for the switch and a closure for the end of the housing, line terminals for connection with line conductors on the outside of said housing at the closed end, a switch in said chamber, connections between the line terminals and the socket terminals one of which is connected through said switch, a cap of insulating material on the end of said housing enclosing the line terminals, and means including a split ring embracing said housing parts for non-rotatably and removably securing said cap to said housing.

5. In an electric socket, a housing, a cap at one end of the housing, a projection on the cap, a projection on the housing, and a ring encircling the cap and housing and having openings into which the projections respectively t for securing the cap to the housing, said openings and projections being circumferentially spaced whereby the cap is nonrotatably held on the housing.

GEORGE B. BENA1\TDER.l 

